Abstract: DC-DC converters, controllers, and control methods include an output stage having a plurality of DC-DC converter circuits connected together in parallel, wherein each DC-DC converter circuit contributes a small amount such as 5% or less of the total output current. Control of the plurality of DC-DC converter circuits may be based on voltage mode control or current mode control, and may include an accelerating mode control in response to a loading transient, or a braking mode control in response to an unloading transient, or a combination of accelerating mode and braking mode control. Embodiments are suitable for low voltage, high current applications such as data center power supplies, and may be readily adapted and scalable to various applications requiring various voltage conversions and output current requirements.

Abstract: Controllers for a 12-switch zero inductor voltage stepdown converter implement at least one switching mode that decreases output voltages first and second phases of the converter to ½ the converter input voltage or less for corresponding first and second selected durations, wherein the output voltages of the first and second phases are phase shifted 180 degrees relative to each other. 5 In one mode the output voltages of the first and second phases are decreased to 0 V for the first and second durations. In another mode the output voltages of the first and second phases are decreased to ½ Vin for the first and second durations. An average output voltage of the converter is reduced in proportion to a time of the first and second selected durations, such that increased step-down ratios are achieved by the 12-switch ZIV converter.

Abstract: A multi-phase power converter includes a printed circuit board having a plurality of conductive layers in a spaced apart and parallel relationship. The plurality of conductive layers includes a plurality of power planes in an interleaved configuration with alternating positive and negative voltages and configured to conduct a relatively high current for supplying to a load. The multi-phase power converter also includes a plurality of switching transistors disposed on an upper surface of the printed circuit board and configured to selectively conduct the relatively high current. The conductive layers include at least one signal plane disposed between the plurality of power planes and a surface of the printed circuit board, the at least one signal plane transmitting signals for controlling operation of the plurality of switching transistors. A power converter phase includes a high-side transistor, a low-side transistor, and a driver circuit disposed adjacent to the transistors.

Abstract: A multi-stage, multi-level DC-DC step-down converter includes a first stage and a second stage having two identical cells connected in parallel. The first stage includes an input capacitor, four switches, and one flying capacitor. The two cells of the second stage each include four switches and one flying capacitor, and an output filter. The cells of the second stage are driven at half the switching frequency of the input stage, and provides a step-down ratio of 4:1. A third stage having four cells may be added to achieve a step-down ratio of 8:1, a fourth stage having eight cells may be added to achieve a step-down ration of 16:1, etc., each additional stage including a doubling of the number of cells connected in parallel, with all cells being substantially identical, and each stage operating at a further reduced fraction of the switching frequency. Embodiments are particularly suitable for applications such as a 48V intermediate bus architecture for servers and datacenters.

Abstract: A multi-stage, multi-level DC-DC step-down converter includes a first stage and a second stage having two identical cells connected in parallel. The first stage includes an input capacitor, four switches, and one flying capacitor. The two cells of the second stage each include four switches and one flying capacitor, and an output filter. The cells of the second stage are driven at half the switching frequency of the input stage, and provides a step-down ratio of 4:1. A third stage having four cells may be added to achieve a step-down ratio of 8:1, a fourth stage having eight cells may be added to achieve a step-down ration of 16:1, etc., each additional stage including a doubling of the number of cells connected in parallel, with all cells being substantially identical, and each stage operating at a further reduced fraction of the switching frequency. Embodiments are particularly suitable for applications such as a 48V intermediate bus architecture for servers and datacenters.